This invention relates to an insulation piercing terminal which is so designed that a covered wire is pushed in between insulation piercing blades whereby the conductor of the wire is connected to the insulation piercing terminal without removal of the insulating sheath of the wire.
FIG. 1 is a perspective view showing a conventional insulation piercing terminal which has been disclosed by Japanese Patent Unexamined Publication No. 193067/1987.
In the conventional insulation piercing terminal, parts of a bottom substrate 2 are cut and bent upwardly to form a pair of insulation piercing plates 3, each of which comprises a pair of insulation piercing blades 11 which defines an insulation piercing slot 12. The pair of insulation piercing plates 3 are set close to each other, to provide insulation piercing pieces 10.
A wire is connected to the insulation piercing terminal 1 as follows: That is, the wire is pushed in the insulation piercing slots 12 from above. As a result, the insulation piercing blades 11 cut the insulating sheath of the wire, and contact the conductor of the wire. When the wire is further pushed in, the conductor of the wire is moved into a space between the right and left insulation piercing blades, so that the conductor is more positively held by the right and left insulation piercing blades 11. In this operation, a force acts to move the crimping plates 3 in opposite directions along a longitudinal axis of the bottom substrate 2.
In general, an insulation piercing terminal is mass-produced, and a number of insulation piercing terminals are built in a connector housing in such a manner that they are adjacent to one another. Hence, there has been a strong demand for the provision of an insulation piercing terminal which is small in size, and light in weight. In order to decrease the weight of the insulation piercing terminal, it is essential to reduce the thickness of a metal plate which is formed into the insulation piercing terminal. In addition, in order to miniaturize the insulation piercing terminal, it is necessary to decrease the width and the length of the insulation piercing terminal. For instance, in order to decrease the width of the insulation piercing terminal, it is essential to decrease the width of the insulation piercing blades forming the insulation piercing slot.
However, if the thickness of the metal plate, which is a raw material for the insulation piercing terminal, is decreased, or if the width of the insulation piercing blades is decreased, then the mechanical strength of the insulation piercing blades is also decreased. As a result, when the wire is pushed in the insulation piercing slot, it acts to move at least one of the insulation piercing plates 3 along a longitudinal axis of the bottom substrate 2.
In the conventional insulation piercing terminal 1, stress concentrates at the bending lines of the roots of the insulation piercing blades 11, so that at least one of the insulation piercing blades 11 move along a longitudinal axis of the bottom substrate 2. This difficulty relates to the fact that the thickness of the insulation piercing plate is decreased by the aforementioned bending operation.